火龙果不同部位发酵后活性成分含量和抗氧化活性

以红心火龙果和白心火龙果为原料,测定不同种类和部位火龙果(红心火龙果果肉,red flesh,RF;白心火龙果果肉,white flesh,WF;红心火龙果果皮,red peel,RP;白心火龙果果皮,white peel,WP)发酵液中总酚、总黄酮含量及抗氧化活性(总抗氧化能力、还原能力和羟自由基清除能力),考察酚类物质含量与抗氧化活性的相关性。结果表明:不同种类和部位火龙果发酵液中总酚、总黄酮含量及抗氧化活性存在显著性差异,且RP发酵液表现出最高的总酚(636.63 mg/L)、总黄酮含量(452.42 mg/L)及最强的总抗氧化能力(相当于V_C浓度169.32 mg/L)、还原能力(140.29 mg/L)和羟自由基清除能力(96.65%);总酚、总黄酮含量与总抗氧化能力、还原能力和羟自由基清除能力之间呈正相关,表明总酚类物质是火龙果中抗氧化成分。

Antioxidant activities of bioactive components in different species and parts of pitayas fermentation

The contents of total phenolics (TPC) and total flavonoids (TFC) and antioxidant activities (total antioxidant capacity, reducing power and hydroxyl radical scavenging activity) in different species and parts of pitayas (red flesh, RF;white flesh, WF;red peel, RP;white peel, WP) fermentation were determined. The correlation between phenolics contents and antioxidant activities was investigated. There were significant differences in the contents of total phenolics and total flavonoids and antioxidant activities among different extracts. The RP fermentation showed the highest contents of total phenolics (636.63 mg/L) and total flavonoids (452.42 mg/L), and total antioxidant capacity (the equivalent of V_C concentration of 169.32 mg/L), and reducing power (140.29 mg/L), and the strongest hydroxyl radical scavenging activity (96.65%). Each bioactive component demonstrated positive correlations with total antioxidant capacity, reducing power and hydroxyl radical scavenging activity, indicating that polyphenols mainly accountted for the antioxidant activities of pitayas fermentation.